2-Hydroxy-4-n-propoxy-5-bromoacetophenone oxime as an Analytical Reagent for Gravimetric Determination of V(V)

• Main Authors: Ambily P. Nair, J. Christine
• Format: Article
• Language: English
• Published: Hindawi Limited 2009-01-01
• Series: E-Journal of Chemistry
• Online Access: http://dx.doi.org/10.1155/2009/129832

2-Hydroxy-4-n-propoxy-5-bromoacetophenone oxime (HnPBAO) was developed as a new analytical reagent for the gravimetric determination of pentavalent vanadium ion. In the pH range 4.0-6.0, the reagent gave a brown coloured precipitate with V(V). Job’s method and Mole ratio method revealed that the stoichiometry of the complex is 1:1 (metal: ligand). Beer’s law is obeyed up to 20.38 ppm of V(V). Molar absorptivity and Sandells sensitivity at 450 nm were found to be 10.22 × 102L/mol/cm and 0.049 µg/cm2 respectively. The stability constant of V(V)-HnPBAO complex is found to be 1.195 × 106. Gibb’s free energy change for complex formation reaction was found to be –8.34 kcal/mol. The reagent can be used for the analysis of vanadium in ferro-vanadium alloys.